I think having a track from 1-9 with an opaque counter would be fine. I guess translucent counters work, but if you're using opaque counters, merely looking to the side of the counter shows your position (e.g. the number to the left is one less than the number you have). I think having the numbers going up helps as well, as seeing it's slightly counter-intuitive to have numbers going down when you're getting more of something. Timer tracks counting down work well, because you're losing time, but this is a resource track.

I totally agree with Pe-ads. There's already a standard on how tracks work, and nobody seems to have much trouble with the tokens hiding the actual value they are marking. Using the value on the right seems really confusing to me.

If you're worried about the values being covered by the tokens, just place the values above or below the place for the tokens:

The bottom track, with opaque or translucent counter. I can't think of a single game where you are accumulating something and the track counts down the remaining amount rather than the amount you have obtained, nor can I think of any games where the amount you have is NOT the space the token is actually in. Deducing that an opaque counter is covering the "3" based on the adjacent numbers is trivial and second-nature, I think.

If it has to be a track, i´d also say seo´s is the best.
Does alwast the same thing happen if you reach 9?
Than you could use another way, not mentioned in the previos thoughts.
Cover a Sympol that shows the happening with 9 tokens you remove step by step. If it is finaly revealed, it happens.

Thank for the comments. It is true that seo's track is much more clear, but some times you want to optimize the space you have so I try to be the most compact possible. Still I think I could manage to setup a track like this.

If you want it more compact, and your tokens are round, you can just place the values on the corners:

But has already been mentioned, even if you cover the current value with the token, when the values grow in steps of one, it's quite obvious that a token between the 2 and the 4 means 3 (and that lets you use a larger font size for better readability).